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991.
992.
We investigated the dietary habits of the polkadot skate, Dipturus chinensis (Japanese name: Gangi-ei), in the East China Sea by analyzing the stomach contents of 529 individuals. Of these, 18 (3.40%) had empty stomachs. The mean and maximum fullness indices (FIs) were 0.67% and 6.12%, respectively. The mean FI of female skates > 500 mm in total length (TL) was higher than that of males and smaller females. The most dominant prey category was crustaceans, which included shrimps, crabs, and anomurans, followed by fishes. Cephalopods were additionally observed. Dipturus chinensis fed on a wide variety of crustacean taxa, and among them, Caridea and Galatheidae were particularly common. Fishes that could be identified were mostly demersal fishes, such as Callionymidae, Triglidae, and Rajidae. Some juvenile D. chinensis were also observed, indicating that cannibalism occurs in this species. Even though dental sexual dimorphism was observed in large size classes (mainly > 500 mm TL), the diet of males and females significantly overlapped. Size-related dietary shifts from small crustaceans, such as shrimps and anomurans, to relatively fast-swimming prey, such as fishes, crabs, and cephalopods, were observed in all seasons. The composition of these prey categories varied among seasons. Shannon–Wiener diversity indices calculated for each size class ranged from 2.01 to 2.51, indicating D. chinensis are generalist predators. As size increased, trophic level increased from 3.58 to 3.85, indicating that larger specimens are at a slightly higher trophic level than smaller specimens. These results suggest that D. chinensis are middle-trophic-level generalist predators that utilize diverse prey depending on their size and the season, and thus play an influential role in the demersal ecosystem of the East China Sea. 相似文献
993.
994.
Yohei Sakamoto Takayuki Yamaguchi Nao Yamamoto Hiroshi Nishiura 《Theoretical biology & medical modelling》2018,15(1):9
Background
Unlike the epidemic of yellow fever from 2016 to 17 in Brazil mostly restricted to the States of Minas Gerais and Espirito Santo, the epidemic from 2017 to 18 mainly involved São Paulo and Rio de Janeiro and resulted in multiple international disseminations. To understand mechanisms behind this observation, the present study analyzed the distribution of imported cases from Brazil, 2018.Methods
A statistical model was employed to capture the risk of importing yellow fever by returning international travelers from Brazil. We estimated the relative risk of importation among travelers by the extent of wealth measured by GDP per capita and the relative risk obtained by random assignment of travelers’ destination within Brazil by the relative population size.Results
Upper-half wealthier countries had 2.1 to 3.4 times greater risk of importation than remainders. Even among countries with lower half of GDP per capita, the risk of importation was 2.5 to 2.8 times greater than assuming that the risk of travelers’ infection within Brazil is determined by the regional population size.Conclusions
Travelers from wealthier countries were at elevated risk of yellow fever, allowing us to speculate that travelers’ local destination and behavior at high risk of infection are likely to act as a key determinant of the heterogeneous risk of importation. It is advised to inform travelers over the ongoing geographic foci of transmission, and if it appears unavoidable to visit tourist destination that has the history of producing imported cases, travelers must be strongly advised to receive vaccination in advance.995.
Mariane Maffei Azuma Pooja Balani Heike Boisvert Mindy Gil Kenji Egashira Tsuguno Yamaguchi Hatice Hasturk Margaret Duncan Toshihisa Kawai Alexandru Movila 《Biochemical and biophysical research communications》2018,495(4):2383-2389
Ceramidases are a group of enzymes that degrade pro-inflammatory ceramide by cleaving a fatty acid to form anti-inflammatory sphingosine lipid. Thus far, acid, neutral and alkaline ceramidase isozymes have been described. However, the expression patterns of ceramidase isoforms as well as their role in periodontal disease pathogenesis remain unknown. In this study, expression patterns of ceramidase isoforms were quantified by real-time PCR and immunohistochemistry in gingival samples of patients with periodontitis and healthy subjects, as well as in EpiGingivalTM-3D culture and OBA-9 gingival epithelial cells both of which were stimulated with or without the presence of live Porphyromonas gingivalis (ATCC 33277 strain). A significantly lower level of acid ceramidase expression was detected in gingival tissues from periodontal patients compared to those from healthy subjects. In addition, acid-ceramidase expression in EpiGingival? 3D culture and OBA-9?cells was suppressed by stimulation with P. gingivalis in vitro. No significant fluctuation was detected for neutral or alkaline ceramidases in either gingival samples or cell cultures. Next, to elucidate the role of acid ceramidase in P. gingivalis-induced inflammation in vitro, OBA-9?cells were transduced with adenoviral vector expressing the human acid ceramidase (Ad-ASAH1) gene or control adenoviral vector (Ad-control). In response to stimulation with P. gingivalis, ASAH1-over-expressing OBA-9?cells showed significantly lower mRNA expressions of caspase-3 as well as the percentage of Annexin V-positive cells, when compared with OBA-9?cells transduced with Ad-control vector. Furthermore, in response to stimulation with P. gingivalis, ASAH1-over-expressing OBA-9?cells produced less TNF-α, IL-6, and IL1β pro-inflammatory cytokines than observed in OBA-9?cells transduced with Ad-control vector. Collectively, our data show the novel discovery of anti-inflammatory and anti-apoptotic effects of acid ceramidase in host cells exposed to periodontal bacteria, and the attenuation of the expression of host-protective acid ceramidase in periodontal lesions. 相似文献
996.
Fumi Ota Tetsuya Hirayama Yasuhiko Kizuka Yoshiki Yamaguchi Reiko Fujinawa Masahiro Nagata Hendra S. Ismanto Bernd Lepenies Jonas Aretz Christoph Rademacher Peter H. Seeberger Takashi Angata Shinobu Kitazume Keiichi Yoshida Tomoko Betsuyaku Kozui Kida Sho Yamasaki Naoyuki Taniguchi 《Biochimica et Biophysica Acta (BBA)/General Subjects》2018,1862(7):1592-1601
Background
Langerin, a C-type lectin receptor (CLR) expressed in a subset of dendritic cells (DCs), binds to glycan ligands for pathogen capture and clearance. Previous studies revealed that langerin has an unusual binding affinity toward 6-sulfated galactose (Gal), a structure primarily found in keratan sulfate (KS). However, details and biological outcomes of this interaction have not been characterized. Based on a recent discovery that the disaccharide L4, a KS component that contains 6-sulfo-Gal, exhibits anti-inflammatory activity in mouse lung, we hypothesized that L4-related compounds are useful tools for characterizing the langerin-ligand interactions and their therapeutic application.Methods
We performed binding analysis between purified long and short forms of langerin and a series of KS disaccharide components. We also chemically synthesized oligomeric derivatives of L4 to develop a new high-affinity ligand of langerin.Results
We show that the binding critically requires the 6-sulfation of Gal and that the long form of langerin displays higher affinity than the short form. The synthesized trimeric (also designated as triangle or Tri) and polymeric (pendant) L4 derivatives displayed over 1000-fold higher affinity toward langerin than monomeric L4. The pendant L4, but not the L4 monomer, was found to effectively transduce langerin signaling in a model cell system.Conclusions
L4 is a specific ligand for langerin. Oligomerization of L4 unit increased the affinity toward langerin.General significance
These results suggest that oligomeric L4 derivatives will be useful for clarifying the langerin functions and for the development of new glycan-based anti-inflammatory drugs. 相似文献997.
Genetic characterization of hemagglutinin protein of measles viruses in Hokkaido district,Japan, 2006–2015 下载免费PDF全文
Masahiro Miyoshi Rika Komagome Hiroki Yamaguchi Setsuko Ishida Hideki Nagano Motohiko Okano 《Microbiology and immunology》2018,62(6):411-417
998.
Yuichi Tsuda Kaori Iwasawa Makoto Yamaguchi 《Bioscience, biotechnology, and biochemistry》2018,82(5):856-861
We investigated the respective effects of the acute supplementation of valine, leucine, and isoleucine on metabolism-related markers by administering a swimming exercise test to rats. As a behavioral analysis, we evaluated the effect of valine and that of leucine on spontaneous activity after exercise. Acute supplementation of valine before exercise significantly suppressed the depression of the liver glycogen and the blood glucose after exercise, whereas leucine decreased the blood glucose and isoleucine had no effect. Valine or leucine supplementation significantly decreased the plasma corticosterone level after exercise, while isoleucine had no effect. In the behavioral analysis, valine significantly increased the spontaneous activity after exercise, whereas leucine had no effect. These results indicate that in rats, the acute supplementation of valine, not leucine or isoleucine, is effective for maintaining liver glycogen and blood glucose and increasing spontaneous activity after exercise, which could contribute to the reduction of fatigue during exercise. 相似文献
999.
Kazuko Yamaguchi Ryota Ii Norihiro Itsubo 《The International Journal of Life Cycle Assessment》2018,23(12):2327-2338
Purpose
The objectives of this study are to develop life cycle impact assessment (LCIA) methods that enable an assessment of the impact on the biodiversity by land use categorized in general land use types and to obtain the implications for an assessment of global land use impact, using the methods in the Life Cycle Impact Assessment Method based on Endpoint Modeling (LIME).Methods
Expected Increase in Number of Extinct Species (EINES), which was calculated by summing the increments in extinction risks of each threatened vascular plant species due to land transformation, was used as an indicator of damage to biodiversity. EINES per land use category was calculated using data from the “Threatened Wildlife of Japan, Red Data Book 2nd ed. Volume 8, Vascular Plants” (hereinafter referred to as “RDB”).Results and discussion
The EINES of wetlands and grassland was relatively high. The number of species that were assumed to exist in forestland was large; however, the EINES of forestland was relatively low. It was considered to be influenced by the huge area of forestland in Japan. EINES of other land was also relatively high, and it was considered to be the reflection of the existence of species whose habitat is peculiar, such as limestone areas or high mountains.Conclusions
Damage factors developed for Japan in this study have broad potential application, as they have more general land use categories than those in LIME 1 and 2; however, it will be necessary to develop damage factors in other countries, taking into account threatened species categories and regional differences in the importance of various land use categories. It is also necessary to accumulate detailed data on threatened species across the planet to develop worldwide damage factors.1000.
Mathieu Gautier Junichi Yamaguchi Julien Foucaud Anne Loiseau Aurélien Ausset Benoit Facon Bernhard Gschloessl Jacques Lagnel Etienne Loire Hugues Parrinello Dany Severac Celine Lopez-Roques Cecile Donnadieu Maxime Manno Helene Berges Karim Gharbi Lori Lawson-Handley Lian-Sheng Zang Benjamin Prud’homme 《Current biology : CB》2018,28(20):3296-3302.e7